You mean as far as screenshots and stuff go? Well for starters, going off the CoD tech demo alone you immediately see that models are lower poly and texture resolution is low res compared to in game models from various games on other engines.
I'm gonna need some comparisons for that. Specifics, please
...what point are you trying to get to?
Well first of all I'd just like to see a comparison of everything you keep referencing. I'm not entirely sure, but I don't recall the BC2 character models being all that advanced compared to CoD character models.
The "point" I'm trying to get to is find out exactly why you think the CoD engine is inferior to others.